In cold climates the forming of ice on ships and ship-borne equipment has always been a problem. Under certain weather conditions even land based material can be subjected to severe icing. Apart from the purely safety aspects, icing has always caused spcial difficulties with regard to keeping missiles and torpedoes ready for firing in all types of weather. These types of weapons are dependent on large launching openings which when they are to be fired must be completely free from ice.
In the case of large vessels having access to electric blower and perhaps even high pressure steam it is no great problem to arrange more or less continual de-icing for the most important weaponry. This is not the case on small vessels where the problem is very much greater e.g., missile and torpedo boats, which quite simply do not have access to sufficient energy or, for reasons of space, supplies of energy can not be made accessible in sufficient quantities for conventional de-icing of the doors on missile launchers or torpedo tubes. A possible solution is of course to open the relevant doors with such force that any ice is torn away but this method requires doors and door opening mechanisms specially designed for this purpose. This in turn means that these components would have to be made very much stronger than otherwise would be necessary and this is often quite unthinkable, as the whole weapon system would then be far too heavy and clumsy. For certain types of ship-borne missile launchers it has therefore been chosen to blast away the front doors or cowlings of these weapons but this solution should only be applicable to smaller types of launchers as larger doors which have been blasted away would be a danger even to the mother ship.
Other solutions for blasting away ice using a conventional charge have not been shown to be a satisfactory alternative as doors and door frames must be made so strong that they will not be deformed while at the same time the risk is run that the ships crew and material will be damaged by flying pieces of ice. To remove the ice by chemical means is of course theoretically possible but it requires too much time and it is also a technically complicated procedure.